1. Field of the Invention
The present invention relates to a heat exchanger that includes a counterflow evaporator.
2. Discussion of the Background
Heat exchangers that include evaporators heated by hot gases typically suffer from relatively large size and high cost. Further, evaporators that generate steam at a single pressure typically exhibit poor thermal efficiency because the hot gas contacts the tubing conveying the liquid being evaporated in a cross-flow or parallel flow configuration at a single temperature, the saturation temperature at the pressure of interest. While previous systems and methods have attempted to improve upon steam boiler control and construction, these systems and methods still suffer from the drawback of cross-flow contact between the heating gas and the evaporating liquid.